Florida Research Activities

Strategic Habitat Conservation for Florida Scrub-Jays at Merritt Island National Wildlife RefugeThis project involves the development of a management strategy for oak (Quercus spp.) scrub that will maximize the long-term demographic performance of Florida scrub-jays (Aphelocoma coerulescens). The project focuses on the Happy Creek Scrub Reserve Unit of Merritt Island National Wildlife Refuge, which is an area with an ecological legacy of fire suppression. Although old-growth oak scrub at Happy Creek has largely been restored to the early-successional state preferred by jays, the scrub generally lacks patches of bare ground. Bare ground is thought to mediate the spread of fire, and thus help maintain the heterogeneous height structure that was characteristic of the scrub prior to human settlement. Prescribed burning has not been successful at creating or maintaining patches of bare ground and so tends to produce large areas of short scrub, which act as demographic sinks for scrub-jays. The objective of this project is to determine how creation of bare ground by plowing could supplement prescribed burning to help maintain better habitat conditions for Florida scrub-jays.

SEAMG was created in 2001 for the purpose of achieving a better science-based approach to wildlife conservation and management. The principal mission of the group is “to better integrate research and management for the purpose of improving how natural resource management decisions are made”. As part of this mission, the SEAMG is responsible for exploring and developing quantitative tools that improve and facilitate the integration of research and management. A distinguishing feature of the SEAMG is that it seeks ways to achieve a heightened level of integration between researchers and managers. At this level of integration, management actions themselves are viewed as opportunities for learning through experimentation, and the selection of management actions generally includes compromises between the (possibly) long-term value of learning and the short-term value of achieving more immediate management objectives. However, practical considerations also are expected to constrain the selection of management actions in most, if not all, resource management problems. A truly integrated program of research and management potentially offers great rewards; however, it is far more difficult and more costly to achieve than the more common situation where research is conducted in support of management without any direct involvement in the selection of alternative management actions. The SEAMG is interested in finding ways to achieve higher levels of integration in the activities researchers and managers to improve the decisions in problems of natural resource management and conservation.

In its 10th year, 2010 was a landmark year for the UF/USACE UAS Program. The team now has developed a very reliable, waterproof platform (Nova 2.1) which is totally autonomous including takeoff (hand tossed) and landing. The FAA requirement to fly within 1 nautical mile line of sight required land and water landings in the extensive Everglades and Lake Okeechobee. The payload includes an Olympus 420E digital SLR with a 25 mm pancake lens® delivering images with 2.5 cm resolution and <0.5 m positional accuracy at 100 m altitude. The Nova 2.1 performed 40+ individual flights without incident in 2010.

The Big Bend region in north Florida is perhaps the most pristine yet unprotected estuarine ecosystem in the state and is habitat for the endangered Florida salt marsh vole (Microtus pennyslvanicus dukecampbelli).The life history of this federally endangered animal remains largely unknown due to its relatively recent discovery, rarity and difficulty in trapping. Only 43 individuals have been captured since the first specimen was discovered in 1979. The main goal was document the persistence of M. p. dukecampbelli, which was successful, as two individuals were captured. One sub-adult and one adult male were found on Long Cabbage Key in the Lower Suwannee National Wildlife Refuge (LSNWR). In the summer of 2010, a stakeholder meeting connecting various agencies interested in ecological work in the Big Bend region was facilitated by FCFWRU. Seventeen stakeholders interested in coastal impacts in this area discussed current research and collaborative opportunities. This study paved the way for continued efforts to study M. p. dukecampbelli as well as other coastal salt marsh species and vegetation. This new project is part of a larger collaborative, multi-agency project entitled “A Land of Flowers on a Latitude of Deserts: Aiding Conservation and Management of Florida’s Biodiversity by using Predictions from “Down-Scaled” AOGCM Climate Scenarios in Combination with Ecological Modeling”. It is funded through USGS’s National Climate Change and Wildlife Science Center.

American Alligator Distribution, Size, and Hole Occupancy and American Crocodile Juvenile Growth and Survival

The Water Resources Development Act (WRDA) of 2000 authorized the Comprehensive Everglades Restoration Plan (CERP) as a framework for modifications and operational changes to the Central and Southern Florida Project needed to restore the South Florida ecosystem. A Monitoring and Assessment Plan (MAP) has been developed as the primary tool to assess the system-wide performance of the CERP by the REstoration, COordination and VERification (RECOVER) program. The MAP presents the monitoring and supporting research needed to measure the responses of the South Florida ecosystem to CERP implementation.

At all life stages, crocodilians integrate biological impacts of hydrologic conditions. Florida’s two native species of crocodilians—the American alligator (Alligator mississippiensis) and the American crocodile (Crocodylus acutus)—are important indicators of health of the Everglades ecosystem because research has linked three key aspects of Everglades’ ecology to them: (1) top predators such as crocodilians are directly dependent on prey density, especially aquatic and semi-aquatic organisms, and thus they provide a surrogate for status of many other species, (2) drier (nests) and wetter (trails and holes) conditions created by ecosystem engineers like alligators provide habitat for plants and animals that otherwise would not be able to survive. This increases diversity and productivity of Everglades marshes and, therefore, alligator monitoring can indicate overall health of the marsh (3) the distribution and abundance of crocodilians in estuaries is directly dependent on timing, amount, and location of freshwater flow; crocodiles and alligators exhibit an immediate response to changes in freshwater inputs into the estuaries.RECOVER’s conceptual ecological models identify three major stressors to wetlands that are affecting populations of alligators and crocodiles: (1) water management practices (affecting hydrology); (2) agricultural and urban development (affecting habitat loss and hydrology); and (3) decreased freshwater flow to estuaries (affecting salinity regimes). Results of this proposed MAP project will increase certainty of CEM linkages hypothesizing population responses to the restoration of freshwater flow and salinity patterns in estuaries and the return of more natural hydropatterns in interior wetlands and alligator holes.

As the global climate changes it is likely to have significant effects on coastal habitats and the species that rely on this habitat for survival. Warmer temperatures and rising seas can increase beach erosion, altering oceanographic patterns and influencing sand temperatures. These changes to the coastal environment may greatly affect species such as sea turtles. Sea turtles spend most of their life at sea but rely on the shoreline for one critical life-history phase: nesting. Changes to beach topography, sand temperatures and oceanographic patterns may impact nesting success, change incubation rates and influence nesting site fidelity. Determining the effects of climate change on nesting sea turtles will help provide better management information for this threatened species.Eglin Air Force Base (EAFB) owns approximately 250 hectares along Cape San Blas, Florida. Research conducted by the Florida Cooperative Fish and Wildlife Research Unit from 1994 to 1997 indicated that this property supports the greatest density of loggerhead turtle nesting in the Florida panhandle. In 1998 it was determined that turtles nesting in Northwest Florida are genetically distinct therefore EAFB property on Cape San Blas is critical for the success of this nesting group. Although this region supports a significant group of nesting sea turtles, it has also been determined that Cape San Blas experiences one of the greatest rates of erosion in Florida. Portions of the west beach of Cape San Blas lose approximately 10 meters of sand per year, while sections of the east beach gain about 4 meters per year. These fluxes may increase substantially when influenced by tropical storms.

The ratio of males to females in a population is an important feature of population structure. Sex ratio directly relates to reproductive rate and adaptive capability of a population (Ridley 1993) and is necessary for determining size, status, and dynamics of the population. For all species of sea turtles, basic knowledge of natural existing sex ratios has been missing until recently and is still not complete for most nesting groups. Sex determination of sea turtles is dependent upon the temperature at which the eggs are incubated (Yntema and Mrosovsky 1982). Several features of nesting beaches have been shown to impact incubation temperatures therefore understanding temperatures of the beach in which eggs incubate is critical to our knowledge of sex ratios.Factors influencing temperatures of nesting beaches include beach orientation, position of the nest on the beach, weather conditions, and sand characteristics (Hays et al. 1995, Leslie et al. 1996, Ackerman 1997). Northwest Florida provides reproductive habitat for a small but genetically distinct group of loggerhead turtles. This area is higher in latitude than the more productive nesting beaches on Florida’s east coast and generally has whiter, finer grain sand beaches than the east coast. It is unknown whether these characteristics influence incubation temperatures, and thereby sex ratios of sea turtle nests in Northwest Florida.

Spectral and Response Assessment of Turtle-Friendly Lighting StudyArtificial lighting disrupts the orientation ability of hatchling sea turtles as they crawl from their nest to the sea. Both intensity and wavelength of the light contribute to this disruptive effect. Studies have indicated that loggerhead and green hatchlings will orient towards shorter wavelength light and will have minimal response to longer wavelength light (Witherington 1991; Levenson et al. 2004). Therefore, managers attempting to reduce hatchling disorientation due to artificial lighting have promoted lights with shorter wavelengths such as low-pressure sodium lamps. Currently, low-pressure sodium lamps are the only lamps to be labeled “turtle friendly” by the Florida Fish and Wildlife Conservation Commission. Development of an alternative to the low-pressure sodium lamp that has minimal to no effect on orientation of hatchling turtles would provide options for residents, business owners and energy companies.

Pre-assessment Plan to Determine Potential Exposure and Injuries of Nesting and Hatching Loggerhead Sea TurtlesThe Mississippi Canyon 252 (MC 252) incident is unparalleled in the scope of its potential geographic impact. Marine and estuarine ecosystems from Texas to Florida are in immediate danger. Potential impacts of oil and dispersants on loggerhead turtles range from mortality to sub-lethal stress and chronic impairment, including potential deleterious effects on reproduction and recruitment. Response and cleanup efforts may also cause loggerhead turtle loss and impairment. The purpose of this plan is to determine and quantify exposure and injuries to the nesting adult loggerhead sea turtles that reside in and nest along the shores of the Gulf of Mexico resulting from exposure to MS Canyon 252 oil (hereafter referred to as oil). This study is being conducted in partnership with a separate yet identical project to quantify exposure and injury to adult Kemp’s ridley turtles that nest primarily along the Texas coast. Combined, these two studies will assess nesting turtle impacts along the entire Gulf coast of the United States.

Gopher Tortoise (gopherus polyphermus)Population SurveyThe gopher tortoise (Gopherus polyphemus), unlisted range, is among the U.S. Fish and Wildlife Ecological Services 2008 priorities as a “preclude the need to list” species. This project furthers the Strategic Habitat Conservation process by providing critical information necessary for outcome-based monitoring, planning and management at St. Marks National Wildlife Refuge.